Xerox Phaser 6121MFP Service Manual page 104

Theory of Operation
Tray 2 Paper Empty Sensor
2-62
The Paper Empty Sensor located on the PF Drive Board detects when the tray is
empty. When media is present in the tray, the actuator is raised unblocking the
sensor. When the tray is empty, the actuator drops into the slit in the Lift Plate
blocking the sensor.
At Paper Empty Condition
PF Drive Board
Paper Empty Sensor
Under Normal Conditions
s6121mfp-194
Phaser 6121MFP Service Manual